vfio: put off the allocation of "minor" in vfio_create_group

The next code fragment "list_for_each_entry" is not depend on "minor". With this
patch, the free of "minor" in "list_for_each_entry" can be reduced, and there is
no functional change.

Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This commit is contained in:
Zhen Lei 2015-03-16 14:08:56 -06:00 committed by Alex Williamson
parent a7fa7c77cf
commit 2f51bf4be9

View File

@ -234,22 +234,21 @@ static struct vfio_group *vfio_create_group(struct iommu_group *iommu_group)
mutex_lock(&vfio.group_lock);
minor = vfio_alloc_group_minor(group);
if (minor < 0) {
vfio_group_unlock_and_free(group);
return ERR_PTR(minor);
}
/* Did we race creating this group? */
list_for_each_entry(tmp, &vfio.group_list, vfio_next) {
if (tmp->iommu_group == iommu_group) {
vfio_group_get(tmp);
vfio_free_group_minor(minor);
vfio_group_unlock_and_free(group);
return tmp;
}
}
minor = vfio_alloc_group_minor(group);
if (minor < 0) {
vfio_group_unlock_and_free(group);
return ERR_PTR(minor);
}
dev = device_create(vfio.class, NULL,
MKDEV(MAJOR(vfio.group_devt), minor),
group, "%d", iommu_group_id(iommu_group));